Muscle Strength, Muscle Mass and Physical Impairment in Women with hypermobile Ehlers-Danlos syndrome and Hypermobility Spectrum Disorder.

OBJECTIVES: To evaluate differences in physical impairment, muscle strength, muscle mass and muscle density between patients with hypermobile Ehlers Danlos Syndrome (hEDS), hypermobile spectrum disorder (HSD), and healthy controls. METHODS: Female adults with hEDS (n=20) and HSD (n=23), diagnosed to the most recent criteria, and age-matched healthy controls (n=28) completed the Arthritis Impact Measurement Scale (physical functioning) and performed maximal muscle strength and strength endurance tests of lower and upper limbs (hand grip, posture maintenance, 30 seconds chair rise and isokinetic tests). Muscle mass and density were evaluated by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. RESULTS: No differences in physical functioning and muscle strength were found between adults with hEDS and HSD. Furthermore, no differences in muscle mass and density were observed between the three groups. Nevertheless, when both patient groups were compared to controls, physical functioning, maximal muscle strength and muscle strength endurance were significantly lower (all p<0.001), except for the hand flexors. CONCLUSION: Physical functioning, muscle strength, density and mass did not significantly differ between individuals with hEDS and HSD. Compared to controls, physical functioning and muscle strength (maximal and endurance) were significantly lower. Consequently, (functional) strength training in individuals with hEDS and HSD is necessary.